Hard shell backpack design



FIG. 1 is a front elevational view of a hard shell backpack showing our new design;

FIG. 2 is a right side elevational view thereof, the broken lines illustrationg straps in FIGS. 2, 3, 4, and 7 not forming any part of the claimed design;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a left side elevational view thereof;

FIG. 5 is a top plan view thereof;

FIG. 6 is a bottom plan view thereof; and,

FIG. 7 is a rear perspective view thereof. 

The ornamental design for a hard shell backpack design, as shown and described. 